Sharpcap is a fully featured image capture application for use with a wide range of astronomy equipment. I have used it a few times for lunar and planetary imaging, but for deep sky imaging my personal preference is to use APT instead. That is not meant to indicate that Sharpcap is not good for this purpose - it really is just a personal preference.

My main use of Sharpcap is with just one of its excellent features, specifically its polar alignment tool. This tool takes images from either the main camera or the guide camera when the scope is pointing near to the celestial pole, and guides the user in a simple step by step way to make mount adjustments to ensure the RA axis of the mount is parallel with the Earth's axis of rotation. This is what polar alignment actually means. The result of this is that the telescope mount only has to rotate one axis to keep a selected object framed on the camera sensor.

In simple terms, it works by taking images at two different angles of rotation and calculates the position of the centre of rotation between them. It uses plate solving to calculate the position of the celestial pole based on its detection of star positions in the frames, and then works out the difference between the true pole and the mount's centre of rotation. Finally, the user is assisted in aligning those two points - the true pole and the centre of rotation. When this is done, the mount is polar aligned.

To learn more about Sharpcap you can visit its website.